This is one of multiple videos where I discuss net or network address translation.
In this video, I'm answering a question from Pedro, who's attending my June three Q&A course.
This is the inside global address.
In other words, this is the netted address of that PC.
This is the address of that PC when traffic is sent onto the internet.
So let's do a telnet to 8.828.1.
Let's configure the server for telnet.
At the moment it's got transport input.
None.
So I'm gonna say transport input Telnet.
Back on router three.
Can we telnet to 82822821?
Yes, we can.
And we're on right one.
Now can we ping 82822822.
No, we can't.
Can we ping 8282823?
No, we can't.
Those addresses don't exist.
So at the moment.
We've got one net translation.
This one.
What I'll do now is create another one for the real IP address of the host inside local ten.
Two.
One, two, two, two.
And we'll set the global IP address to 8.8 to 8.2 and make that extendable IP net inside source.
Let's do the same for 3 to 3.
And added to that address.
So show IP.
Net translation we have three net entries in the net table.
At the moment, there are no outside local outside global entries because no traffic is being initiated
by the PC to those servers.
But if we now ping this address, which didn't work in the past, it now works.
And the same is true for 82822823.
So we're getting some ICMP echoes there.
Let's call that.
So 828823 works and or two works.
And if you look at the net translations, we can see the ICMP translations in the table here.
ICMP may be a little bit more difficult to read.
So let me do a telnet.
So telnet it from this PC to the server.
And notice we can see that the destination port is 23.
So support from the PC is a random port number.
So this is the net translation for the telnet session.
Debug IP net if I hit enter here.
We should see translations.
There we go.
And then I'll just type some characters.
Notice we're getting natural translations.
A source of 82822824 going to 8228281 means that the destination address is translated to 10.1 to 1.1,
and then it's translated back for the reverse traffic.
Okay.
So in summary, show run pipe include net.
To set up a network such as this where you have multiple internal servers and you want them to be accessible
from the Internet.
One way to set this up is to create an individual static net entry per server.
This is the real IP address configured on the device.
In other words, that's the address that's being configured on the device.
It's called the inside local address.
This is the inside global address.
This is the netted or virtual IP address associated with this physical IP address configured on the
device.
So Pedro, I'm hoping that answers your question.
I also hope that this helps everyone else.
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I wish you all the very best.